Molecular speed and direction selection

ABSTRACT

A technique of generating a flow from a gas. The technique includes the steps of selecting molecules from the gas on a nanoscopic or microscopic scale, and generating the flow from the selected molecules. The gas can be air. In one embodiment, the molecules are selected based on the direction of movement of the molecules. In another embodiment, the molecules are selected based on the velocities (i.e., direction and speed) of the molecules. Also, devices that implement the technique.

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims priority from Provisional Application No.60/434,852, “Air Flow, Heat Exchange, and Molecular Selection Systems,”filed Dec. 19, 2002, in the name of inventors Scott Davis and ArtWilliams; from Provisional Application No. 60/499,066, “Molecular SpeedSelection, Flow Generation, Adiabatic Cooling, and Other HeteroscopicTechnologies,” filed Aug. 29, 2003, in the name of inventors Scott Davisand Art Williams; and is a CIP of U.S. patent application Ser. No.10/693,635, “Heteroscopic Turbine,” filed Oct. 24, 2003, in the name ofinventor Scott Davis. These applications are incorporated by referenceas if fully set forth herein.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to selecting molecules from air or other gaseousor liquid matter based on the speed or direction of those molecules andgenerating bulk flows from the selected molecules.

2. Description of the Related Art

Molecules in air (and other gaseous matter) are in constant motion,continuously colliding with each other. This molecular motion isconstantly occurring, even if the bulk velocity of the air is zero.

The speed of the molecules between collisions is the thermal velocityfor the air. The average distance between collisions is the mean freepath distance. The overall bulk velocity of the air is the air'stransport velocity. Theoretically, the maximum transport velocity thatcan be imparted to an airflow is the thermal velocity of the underlyingair molecules.

Several conventional apparatuses exist for generating a flow of air.Examples include fans and turbomolecular pumps.

Fans force air to flow in bulk with rotating fan blades. Even highlyefficient fans cannot achieve very high transport velocities compared tothe underlying molecular motion of the air. In particular, even goodfans can only achieve transport velocities that are on the order of ahundredth to a thousandth of the thermal velocity of the air molecules.

Because high-velocity (i.e., comparable to thermal velocity) bulk airflow cannot be achieved with conventional fans, larger fans must be usedto move significant amounts of air. As a result, fan size often becomesa limiting design factor for anything that requires airflow, cooling, orthe like.

Another device for moving air (and other gaseous matter) is theturbomolecular pump. Turbomolecular pumps can be used as absorbers orconsumers of air molecules. These pumps typically are used to drawmolecules from a high vacuum environment in order to create an even“higher” vacuum.

Turbomolecular pumps use rotating turbine blades to select moleculesfrom air. Molecules that randomly cross the tops of the blades arecaptured and whisked away.

In order for existing turbomolecular pumps to operate, collisionsbetween air molecules must be avoided. If such collisions occur, themolecules can bounce away from the blades before they can be captured,defeating the operation of the pump.

Typical existing turbomolecular pumps use macroscopic turbine bladesrotating at extremely high speeds, for example 75,000 RPM. These highspeeds are used so that molecules that cross the path of the rotorblades do not have time to collide with other molecules before beingwhisked away.

Collisions are also prevented by ensuring that the mean free pathdistance for the molecules is not too small compared to the container orfeed tube for the pump. The ratio between container or feed tube lengthand mean free path distance is the Knudsen number.

Typical existing turbomolecular pumps only operate effectively if theKnudsen number is no greater than approximately 10. This Knudsen numbercan only be achieved in a high vacuum, and then with only relativelysmall containers or feed tubes. Obviously, a significant air flow cannotbe generated by pumping from a high vacuum through a small container orfeed tube. As a consequence, existing turbomolecular pumps do notgenerate significant air flow.

All of these problems also exist when generating a flow from any othergas or gas mixture besides air.

Generation of flows from gasses is of interest because such flows areubiquitous in modern technology. For example, heating and coolingapplications generally utilize some type of bulk flow in theiroperation. Examples of these applications include cooling units forcomputers, radiators for cars, air conditioners, refrigerators, heaters,industrial cooling units for large machinery, and innumerable otherdevices.

Conventional techniques for exchanging heat with air involve forcedconvection. In forced convention, air is forced to flow over or throughsome heating or cooling element. For example, air can be blown over orthrough a heated or cooled substrate, duct or grille. The purpose ofthese arrangements can be to heat or cool either the air or thesubstrate, duct or grille.

In all of these arrangements, a boundary layer forms over the surface ofthe substrate, duct or grille. In particular, air molecules in contactwith the surface tend to “stick” to the surface. These air molecules inturn impede the motion of adjacent air molecules in the air flow, whichin turn impede other air molecules. Thus, a region of slow-moving airmolecules forms over the surface. This region is known as a velocityboundary layer.

The velocity boundary layer limits the number of air molecules that comeinto contact with the surface. Actual heat transfer only occurs at thissurface. As a result, once heat is transferred to or from the moleculesin the boundary layer, further transfer of heat is largely blocked. Moreheat can only be transferred once the molecules in the boundary layerare dragged away from the surface by the viscosity of the air, which isan intrinsically inefficient process. Molecular collisions also candrive the molecules away from the surface, but this is an even moreinefficient process. As a result, the velocity boundary layer isaccompanied by a thermal boundary layer.

The thermal boundary layer greatly impedes the transfer of heat betweenthe forced air and the substrate, duct or grille. In addition, theforcing elements (e.g., fans) for conventional heat transfer devicesmust be powerful enough to overcome the viscosity of the air. Otherwise,little heat transfer will occur. Because of these factors, heating andcooling units tend to be fairly large devices with large footprints.These large footprints are the limiting design factors in many moderndevices.

One alternative technique that has been explored with little success isheating or cooling the blades of fans that force (i.e., blow) air.However, in this approach, a thermal boundary layer forms on a fan'sblades. As a result, this approach is no more efficient than forcing airover or through a substrate, duct or grille. All of these problems alsoexist when transferring heat to or from any other gas or gas mixturebesides air.

SUMMARY OF THE INVENTION

Accordingly, great benefit could be derived from devices and methodsthat more efficiently generate bulk flows from a gas, for example forheating and cooling applications.

The invention addresses this need with a device that exploits thephysics of molecular movement on a microscopic or nanoscopic scale toselect molecules based on their directions or directions and speeds. Theselected molecules are then aggregated into one or more bulk flowsuseful on a macroscopic scale. The use of microscopic or nanoscopicprinciples to generate macroscopic effects is referred to as“heteroscopic” in this disclosure.

The heteroscopic nature of the device helps improve efficiency. Themicroscopic or smaller (e.g., nanoscopic) structures allow segregationof molecules in a gas based on the thermal speed of those molecules. Thesegregation can occur with little or no work done on the selectedmolecules. Thus, the process of segregation expends a relatively lowamount of energy, especially compared to traditional heating and coolingtechniques. Aggregation of selected molecules into bulk flows permitsapplication of the invention to real-world macroscopic heating andcooling applications.

If the molecules are selected based on speed as well as direction, inother words based on velocity, then the generated flow can besignificantly cooler or hotter than the gas from which the flow isgenerated. Thus, the invention provides a viable alternative toinefficient heating and cooling techniques such as forced convection.

Accordingly, one embodiment of the invention is a technique ofgenerating a flow from a gas. The technique includes the steps ofselecting molecules from the gas on a nanoscopic or microscopic scale,and generating the flow from the selected molecules. The gas can be air.

In one embodiment, the molecules are selected based on the direction ofmovement of the molecules. In another embodiment, the molecules areselected based on the velocities (i.e., direction and speed) of themolecules.

Preferably, the molecules are selected from the gas at higher thannear-vacuum pressure, for example at atmospheric pressure.

The molecules can be selected by nanoscopic or microscopic blades movingat a velocity comparable to a mean thermal velocity of the molecules inthe gas. In one embodiment, the blades are mounted on or in a rotatingstructure such as a circular airfoil. In another embodiment, the bladesare mounted on or in a surface movable substantially linearly throughthe gas such as a radiator of a vehicle.

The blades can be protruding blades or alternatively can be formed frommicroscopic or nanoscopic holes in a substrate. Other types of bladesand/or edges can be used.

The invention also encompasses devices that implement the foregoingmethods.

This brief summary has been provided so that the nature of the inventionmay be understood quickly. A more complete understanding of theinvention may be obtained by reference to the following description ofthe preferred embodiments thereof in connection with the attacheddrawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIGS. 1A and 1B show rotating surfaces that can be used to implement theinvention.

FIG. 2 shows surfaces that move substantially linearly through a gas toimplement the invention.

FIG. 3 shows a possible arrangement of blades for direction selection ofmolecules.

FIG. 4 shows forced convention in the arrangement show in FIG. 3.

FIG. 5 shows blades formed from holes in a surface of a rotor or otherstructure.

FIG. 6 shows another possible arrangement of blades for directionselection of molecules.

FIGS. 7 to 9 show possible ducting arrangements.

FIGS. 10A to 10C show a possible arrangement of blades for selectingmolecules based on velocity (i.e., direction and speed). FIGS. 10A to10C are referred to collectively as FIG. 10.

FIGS. 11A and 11B show some possible variations on the arrangement shownin FIG. 10. FIGS. 11A and 11B are referred to collectively as FIG. 11.

FIGS. 12 to 14 show more possible arrangements of blades that performvelocity sorting of molecules in a gas.

FIG. 15 shows a potential problem caused by hotter molecules movinglaterally across blades in a device that performs velocity sorting.

FIGS. 16 to 18 show possible solutions to the problem shown in FIG. 15.

FIG. 19 shows a possible aggregation and ducting arrangement for usewith rotor-based speed selection.

FIGS. 20 and 21 show possible modifications for blade arrangements thatperform speed selection.

FIGS. 22A to 22D illustrate an embodiment that includes a rotor (disk)arranged between two stators. FIGS. 22A to 22D are referred tocollectively as FIG. 22.

FIG. 23 shows a possible variation of the arrangement shown in FIG. 22.

FIGS. 24A to 24C show possible features for an output stator for adevice that performs velocity sorting. FIGS. 24A to 24C are referred tocollectively as FIG. 24.

FIG. 25 shows a possible aggregation and ducting arrangement for therotor/stator embodiment.

FIGS. 26 to 28 show possible variations of the rotor/stator embodiment.

DESCRIPTION OF THE PREFERRED EMBODIMENT

Lexicography

Nanoscopic: Having lengths or dimensions less than or equal to abillionth of a meter.

Microscopic: Having lengths or dimensions less than or equal to onemillimeter.

Macroscopic: Having lengths or dimensions greater than or equal to onemillimeter, and numbers greater than about one hundred.

Heteroscopic: Characterized by use of microscopic or nanoscopicprinciples to generate macroscopic effects.

Transport speed: The mean speed of an flow of gaseous matter moving inbulk. Also called bulk speed.

Mean thermal velocity: The speed of molecules in gaseous matter.

Mean free path distance: The average distance that molecules in gaseousmatter travel between collisions with other molecules in the gaseousmatter.

Hotter molecules: In reference to a given gas, hotter molecules consistof an aggregation of molecules selected from the gas that have a meanthermal velocity faster than the mean thermal velocity of the gas. Inreference to individual molecules, a so-called hotter molecule isexpected, on average, to be faster and therefore hotter than a so-calledcooler molecule, but exceptions can occur.

Cooler molecules: In reference to a given gas, cooler molecules consistof an aggregation of molecules selected from the gas that have a meanthermal velocity slower than the mean thermal velocity of the gas. Inreference to individual molecules, a so-called cooler molecule isexpected, on average, to be slower and therefore cooler than a so-calledhotter molecule, but exceptions can occur.

Near vacuum conditions: Pressures less than or equal to 0.001atmospheres.

Knudsen number: A ratio of pump container or feed tube size to mean freepath distance. (Sometimes in scientific literature, the Knudsen numberis expressed as the opposite ratio.)

Blade: Broadly, any edge that is moved through air. This termencompasses both flat blades and tops of holes in a moving surface.

Comparable: In this application, speeds and distances are comparable ifthey are within an order of magnitude of each other. For example, if airmolecules have a mean thermal velocity of 500 meters per second, bladesmoving at 50 to 5,000 meters per second would be moving at speedscomparable to the mean thermal velocity of the air molecules. Throughoutthis disclosure, the term “on an order of” is synonymous to “comparableto.”

Heteroscopic Effects

The techniques of the invention simultaneously operate on two differentscales. First, molecules are selected or segregated from a gas on amicroscopic or nanoscopic scale. In particular, the structures thatselect the molecules have dimensions comparable with the mean free pathdistance of the molecules in the gas. In normal operating conditions,for example regular atmospheric pressure, these dimensions are somewherebetween microscopic and nanoscopic. The invention is not limited to suchoperating conditions.

Second, macroscopic effects are used. For example, the segregatedmolecules converge or are directed to generate a bulk flow. The bulkflow can be created from the segregated molecules by the arrangement ofthe segregating structures, by use of macroscopic structures such asflow ducts, by some combination of these arrangements, or by some otherstructures or techniques.

The invention preferably operates with a Knudsen number less than tenand preferably between one half and two (i.e., near unity). Thus, bladesor edges used to select molecules are preferably about a mean free pathdistance high and spaced apart by about the mean free path distance. Themean free path distance is for a gas at a pressure at which the deviceis intended to operate. According to the invention this gas and pressurecan be, but is not limited to, air at normal atmospheric pressure.

In more efficient embodiments of the invention, the microscopic ornanoscopic structures do little or no actual work while segregatingmolecules based on their speeds. Instead, molecules on an input sidemoving within a particular range of speeds and directions can passthrough the structures, while other molecules collide with thestructures or are otherwise repelled.

On an output side, a bulk flow generated by the aggregation of theselected molecules serves to push other ambient molecules out of theway. In systems that do not generate such bulk flows, “infidel”molecules entering from the output side can force the systems to dosignificant extra work. In the invention, the momentum of moleculescomprising the bulk flow pushes would-be infidels away from the outputside, thereby helping to prevent those molecules from colliding with thestructures and forcing them to do work.

In the preferred embodiment, this bulk flow is aggregated molecular flowat thermal speeds. This differs from conventional prior art systems, inwhich the bulk flow is caused by fan or turbine blades actually pushingand therefore working on the molecules. Thus, by pushing away infidels,the bulk flow of the invention reduces one of the only remaining sourcesof work for the blades to perform, greatly improving efficiency.

The combination of microscopic or nanoscopic selection with aggregationinto a macroscopic bulk flow can lead to extremely high efficiency. Thisefficiency arises in part from a lack of a velocity boundary layer at aninterface between a gas and the blades. This leads to lower viscouslosses. The invention is not limited to embodiments that lack such aboundary layer, although the preferred embodiment does lack the boundarylayer.

Until recently, the combination of a large number of microscopic andsmaller segregating structures has been limited to fields that deal withelectricity, light, or other energy. One example of such heteroscopicdevices is a computer chip.

In sum, the heteroscopic nature of the invention enables high efficiencywithout creating significant barriers to production. Such efficiencyshould have important ramifications for applications such as generatingbulk flows, including for example applications where fans and jets areused, and heating and cooling other devices and elements. The inventionis not limited to these applications—other applications exist.

Macroscopic Mounting

FIGS. 1A and 1B show rotating structures (i.e., rotors) on or in whichblades or edges can be mounted for direction or velocity selection ofmolecules from a gas. Such a rotor could be, but is not limited to, aheteroscopic turbine. In these figures, the rotors spin about an axisextending out of the figures.

In FIG. 1A, rotor 1 in a shape of a disk or annulus contains chips 2.The chips contain the microscopic or nanoscopic blades.

The rotor can include ports or ducts (not shown) below each chip 2 topermit airflow from the chips to pass through the rotor. Ports or ductsalso can extend radially for speed selection embodiments (see below).Alternatively, the arrangements of the blades themselves could result insuch bulk flows without a need for ducting.

The Knudsen number for the rotor in FIG. 1A preferably is less than ten,for example between one half and two. Each of the blades has a heightcomparable to the mean free path distance for the gas in which thedevice operates, and the blades spaced apart by a distance comparable tothe mean free path distance. In operation, the rotor preferably rotatesfast enough so that the blades move through the surrounding gas at aspeed comparable to the mean thermal velocity of the gas.

For example, in air at normal atmospheric conditions, the mean free pathdistance is 6.91E−08 meters. In one embodiment, the gap between bladesis 3.455E−08 meters, and the height of the blades is also 3.455E−08meters. In this embodiment, if the annulus has a circumference of 4meters, then in operation it would preferably rotate at 7,500 RPM.Somewhere on the order of 1.75E+13 such blades could easily by placed onthe annulus shown in FIG. 1A, resulting in significant aggregate flowfrom the blades. The invention is not limited to these particularnumeric values, which are only provided as an example of a preferredembodiment.

The arrangement in FIG. 1A permits the blades to be fabricated on thechips, for example using technology developed for computer chipmanufacturing. Then, the chips can be attached to the rotor. One benefitof this arrangement is that a manufacturing defect in one chip onlyruins that chip, not the entire rotor. This can greatly reducemanufacturing costs.

FIG. 1B shows another embodiment of a rotating structure (i.e., rotors)on or in which blades or edges can be mounted for direction or velocityselection of molecules from a gas. In this embodiment, the blades areattached directly in or on the rotor 3. The locations of blades arerepresented by the dashes around the periphery of the rotor or disk. Theadvantage of this arrangement is that far more blades might be attachedor manufactured into the rotor.

In both FIGS. 1A and 1B, the blades preferably are arranged on the outerportion of the rotor or disk to take advantage of higher linearvelocities that occur there as compared to nearer the axis of the rotoror disk. Other arrangements can be used, including ports or other inputstructures placed over the entire surface of the rotor or disk.

FIGS. 1A and 1B define conventions for “radial view” and “tangentialview” used throughout this disclosure. Namely, a “radial view” is aview, possibly a cross-section, along a radius of the rotor or disk. A“tangential view” is a view, possibly a cross-section, parallel to atangent to the rotor or disk.

FIG. 2 shows surfaces 4 that move substantially linearly through a gas,as represented by the arrow in the figure, to select or sort moleculesbased on direction or speed (velocity). The term “substantiallylinearly” is intended to represent movement on the scale of thestructures themselves. For example, if the structures were part of ormounted on a radiator in a vehicle, the movement of the vehicle down aroadway would be “substantially linear,” despite turns or curves in theroadway.

The locations of blades mounted in or on these surfaces are representedby dashes on the surfaces. In an alternative embodiment, the bladescould be mounted on chips that are in turn mounted on or in thesurfaces.

The structures in FIG. 2 can include ports or ducts (not shown) belowthe blades to permit airflow from the chips to pass through. These ductsor ports can be used to aggregate selected molecules into bulk flows.Alternatively, the arrangements of the blades themselves could result insuch bulk flows without a need for ducting.

The Knudsen number for the arrangement in FIG. 2 also preferably is lessthan ten, for example between one half and two. Each of the blades has aheight comparable to the mean free path distance for the gas in whichthe device operates, and the blades spaced apart by a distancecomparable to the mean free path distance. In operation, the surfacespreferably are moved through a gas at a speed comparable to the meanthermal velocity of the gas, although this need not be the case.

Direction Selection

FIG. 3 shows a possible arrangement of blades for direction selection ofmolecules. The number and arrangement of blades in FIG. 3, as well asthroughout the rest of this application, are not to scale.

The blades in FIG. 3 could be mounted on the chips, rotors, or surfacesshown in FIGS. 1A, 1B and 2, or on some other devices that moves througha gas, either rotationally or translationally. If the blades are mountedon a rotor, then FIG. 3 is a radial view.

In FIG. 3, blades 5 are of approximately equal height. The blades are onan order of a mean free path distance high and are on an order of a meanfree path distance apart. The Knudsen number for these blades preferablyis near unity.

When the blades move through a gas at a speed comparable to the meanthermal velocity of the gas, molecules that move past the tops of theblades are captured. Molecules moving away from the tops are notcaptured. Thus, the tops of the blades form direction selection plane 6.

Molecules captured by blades 5 either pass through the blades untouchedor are pushed by the blades to below the blades. The aggregation ofthese molecules generates bulk flow 7.

While the flow generated by each blade is small, the aggregation of allof the flows can be very significant. In fact, depending on theparticular embodiment, the bulk flow can be much stronger than would begenerated by a similar sized conventional fan or turbine. In theory, theflow can even be strong enough to provide jet propulsion for a vehiclefrom even a relatively small device.

The momentum of molecules comprising the bulk flow pushes would-beinfidels away from the output side of the blades (i.e., bottoms in FIG.3), thereby helping to prevent those molecules from colliding with thestructures and forcing them to do (more) work.

FIG. 4 shows forced convention that can result from direction selection.As molecules are captured from the top side of blades 5, other moleculesmove via Brownian motion to take their place. Hotter molecules arefaster and therefore more likely to take the place of capturedmolecules. As a result, more hotter molecules tend to be captured,resulting in flow 7 including a disproportionate number of hottermolecules (i.e., a hotter flow is generated). This process is called“forced convection” and may have many useful applications, for examplecooling gas above the device or warming gas below the device.

FIG. 5 shows blades formed from holes in a surface of a rotor or otherstructure. These holes could be in the chips, rotors, or surfaces shownin FIGS. 1A, 1B and 2, or on some other structure that moves through agas, either rotationally or translationally. If the holes are in arotor, FIG. 5 is a radial view, and the rotor surface is moving fromleft to right.

The edges and sides of holes 9 in FIG. 5 form blades. In a preferredembodiment, the size of holes 9 is greater than a molecular size for thegas in which the device operates and less than a mean free path distancefor that gas.

The holes in FIG. 5 can be bored using any of a great number of existingtechnologies, including but not limited to e-beam and photographiclithography, sputtering, laser drilling, mechanical drilling, ion beamdrilling, chemical etching, and other technologies.

FIG. 6 shows another possible arrangement of blades for directionselection of molecules from a gas. Blades 11 in this embodiment areformed from angled planes projecting from the surface of the rotor orother structure. Molecules captured by blades 11 exit through openings12 at angles formed between the planes and the surface.

FIGS. 7 to 9 show possible ducting arrangements for use with the bladesand other structures shown herein. FIG. 7 has ducts 13 that collectcaptured molecules for radially exit from a rotator-based device onwhich the blades are mounted. FIG. 8 has ducts 14 that collect capturedmolecules for axial (downward) exit from such a device. Other ductingarrangements are possible, some of which are shown in other figures inthis disclosure.

FIG. 9 shows a twisted of curved duct that can be used with some of theducting arrangements. This duct forces molecules that pass through it tocollide with the walls of the duct. The result can be to slow themolecules down, thereby cooling them. Molecules can even be slowed downby one or more collisions with the blades.

Speed Selection

In general, the term speed refers to a scalar quantity, while velocityrefers to a vector that incorporates both speed and direction. However,in some instance in this application, the term “speed selection” is usedinterchangeably with “velocity selection,” with both terms meaningselection, sorting or segregation of molecules from a gas based on theirvelocities.

When molecules are selected from a gas based on their velocities, theaggregations of those molecules can result in flows with differenttemperatures. Thus, techniques and devices of the invention can be usedto generate hotter or cooler flows from a gas. These embodiments can beextremely efficient.

In mathematical terms, let ? W be an amount of work done on molecules ina gas, and let ? V be a mean difference in speed between “hot” and“cold” molecules in hot and cold bulk flows generated by theseembodiments. In the more efficient preferred embodiments, ? W/? V can beless than 3.1. Before the invention, a device that achieved thisrelationship between work and molecular speed had not been realized. Ofcourse, the invention is not limited to embodiments that exhibit thishigh efficiency.

FIGS. 10A to 10C show a possible arrangement of blades for selectingmolecules based on velocity and therefore temperature. FIGS. 10A to 10Care referred to collectively as FIG. 10.

Briefly, the blades in FIG. 10 have at least two different heights. Whenthe blades are moved through a gas, tops of the blades having a firstheight form a direction selection plane that filters molecules thatcross the plane, and tops of blades having a second height form a speedselection plane that filters molecules based on thermal velocity.

In FIG. 10, blades 30 and 31 preferably are microscopic or evennanoscopic in size. Blades 30 and 31 preferably are mounted on a rotoror other structure and are angled in a direction of blade movementthrough a gas. Some of the blades are longer than others. In FIG. 10,blades 30 are longer than blades 31.

If the blades are mounted on a rotor or disk (e.g., turbine), that rotoror disk preferably rotates fast enough such that the blades are movedthrough the gas at a speed comparable to the mean thermal velocity ofthe gas. The spacing between blades preferably is comparable to the meanfree path distance of the molecules in the gas. Thus, the arrangement ofblades on a particular rotor preferably is matched to a range ofmolecular speeds and mean free path distances corresponding to aparticular range of temperatures and pressures of a gas.

The angle of the blades preferably is chosen based on the mean speed ofmolecules in the gas, which in turn is dependent upon the temperatureand pressure of the gas, and the speed at which the blades move throughthe gas. In some embodiments, the ambient temperature and pressure ofthe gas can be controlled to best match the angles of the blades.

The tops of the longer blades form a direction selection plane.Molecules of a gas that cross this plane will be whisked away by theblades. Likewise, the shorter blades form a speed selection plane. Onlymolecules traveling with a certain vertical speed (and thereforetemperature) will be cross this plane in time to be captured by theshorter blades. Stated differently, only molecules moving fast enough tohave a sufficiently short time of flight from the direction selectionplane to the speed selection plane will be selected by the shorterblades.

FIG. 10 shows direction selection plane 32 and speed selection plane 33.Also shown in FIG. 10 are two molecules represented by small circles.The empty circle represents a hotter and therefore faster (at least inthe vertical direction) molecule. The filled circle represents a coolerand therefore slower (at least in the vertical direction) molecule.

In FIG. 10A, neither of the molecules has crossed the directionselection plane. In FIG. 10B, the molecules have traveled sufficientlyfar downward that they have crossed direction selection plane 32. Of thetwo molecules, only the hotter molecule has enough downward speed tocross speed selection plane 33 before the closest smaller blade 31passes by due to motion of the blades (i.e., spinning of the rotorholding the blades). Thus, slower (cooler) molecules and faster (hotter)molecules are segregated as shown in FIG. 10C.

In operation, some faster molecules will be moving in a direction thattakes them to the same side of the shorter blade as slower molecules.Thus, the cooler molecules might be “contaminated” with at least somehotter molecules. However, only hotter molecules will have sufficientspeed to pass the speed selection plane in time to be grouped on thehotter molecule side. Thus, the mean speed (temperature) of the hottermolecules will tend to be higher than that of the cooler moleculesdespite any contamination.

Once the molecules have been segregated, like molecules can beaggregated using macroscopic ducts to generate bulk flow. Alternatively,like molecules selected by many blades can simply exit in the samedirection, for example below a rotor with the blades, thereby creating abulk flow without the need for any ducts. In any case, further ductingcan be used to aggregate or redirect any flow.

A very large number of blades preferably select molecules for each flow.In a preferred embodiment, on the order to 10^12 or more blades can beused. For example, and without limitation, one preferred embodiment uses1.75E+13 blades. The invention is not limited to this number of blades.

In terms of “slip,” the device in FIG. 10 can be modeled as a perfect ornearly perfect absorber of molecules that cross the direction selectionplane. Therefore, no (or few) molecules stick to the blades, ensuringadequate slip between the blades and the gas molecules. Slip not aconcern at the output (not shown) of the device due to the bulk natureof the output flow.

FIGS. 11A and 11B show some possible variations on the arrangement shownin FIG. 10. FIGS. 11A and 11B are referred to collectively as FIG. 11.

FIG. 11A shows capture duct 34 for cooler molecules, and capture duct 35for hotter molecules. Capture duct 35 in turn feeds macroscopic duct 36for aggregating and transporting the hotter molecules away.Transportation of the cooler molecules is not illustrated in FIG. 11A.

In some cases, only hotter or cooler bulk flows are desired. In thiscase, a reflection surface can be added to the device to block undesiredmolecules. Reflection surface 37 adjoining the trailing blade in FIG.11B is such a surface. In the embodiment shown in FIG. 11B, no ductingis used to aggregate the selected molecules. Rather, the hottermolecules selected by many blades aggregate below the rotor or otherelement on which the blades are mounted. Of course, ducting can be usedif so desired.

FIGS. 12 to 14 show more possible arrangements of blades that performspeed selection of molecules in a gas.

FIG. 12 shows blades formed from angles planes. Hotter molecules passthe direction selection plane formed by the tops of taller blades 40 andpass through the blades before being blocked off by shorter blades 41.Thus, hotter molecules can exit below the blades. Cooler molecules canbe directed by a channel formed between each blade 40 and each blade 41for exit radially from the blades.

FIG. 13 shows blades formed from angled planes with bases. The bladesare stacked in layers. Blades 43 on a top layer preferentially capturecooler molecules. Blades 44 on a bottom layer preferentially capturehotter molecules. Ducting can be provided to transport the moleculesaway, for example for aggregation into bulk flows.

FIG. 14 shows blade 46 formed from an angled planes projecting from asurface, akin to the blade shown in FIG. 6. This blade has openings 47for cooler molecules to pass at angles formed between the planes and thesurface, and openings 48 for hotter molecules to pass through thesurface.

Other blade arrangements can be used to perform speed selection ofmolecules in gas.

FIG. 15 shows a potential problem caused by hotter molecules movinglaterally across blades during sorting. In FIG. 15, hotter molecule 50that moves laterally across the blades passes into an area that issupposed to sort out cooler molecules. FIGS. 16 to 18 show possiblesolutions to this problem.

In FIG. 16, baffles 52 between rows of blades help prevent lateralmotion of hotter molecules into cooler molecule areas.

In FIG. 17, three rows of blades that capture hotter molecules aresurrounded by rows of blades that capture cooler molecules. Thus, anylaterally moving molecules will tend to be captured by the blades forhotter molecules.

To combine the arrangements in FIGS. 16 and 17, baffles could be placedbetween sets of rows of blades such as those shown in FIG. 17. In otherwords, every five (or some other number) of rows of blades could beseparated by baffles.

Yet another solution is to curve the blades concavely in a direction oftheir motion through a gas. This solution is illustrated in FIG. 18,which shows curved blades 53. The curved sides of the blades would tendto reflect laterally moving molecules, as illustrated by the angledarrow in the figure.

Other solutions and arrangements are possible without departing from theinvention.

FIG. 19 shows a possible aggregation and ducting arrangement for usewith rotor-based speed selection.

In FIG. 19, molecules are segregated by blades on rotor 54. Ducting orother structures redirect the molecules based on their speed (i.e.,temperature). Output stator 55 includes preferably macroscopic ductingto aggregate and to transport faster (i.e., hotter) molecules belowrotor 54. Output stator 55 also includes preferably macroscopic ductingto aggregate and to transport slower (i.e., cooler) molecules radiallyfrom rotor 54.

FIGS. 20 and 21 show possible modifications for blade arrangements thatperform speed selection.

In the foregoing speed selection embodiments, molecules are segregatedinto two groups: hotter and cooler. However, molecules can be segregatedinto plural different groups based on their velocities. To this end,FIG. 20 shows plural blades 65 to 69 of different heights disposedbetween blades 70 that define a direction selection plane. When theseblades move, for example by rotation of a rotor on which they aremounted, the blades will select plural different speeds of molecules.Only the fastest molecules will reach the leading shorter blade 65. Theslowest will reach the trailing longer blades, possibly contaminatedwith faster molecules. When the molecules are aggregated, those caughtby leading shorter blades will tend to be faster and therefore hotterthan those caught by trailing longer blades.

Again, the angle of these blades preferably is chosen based on the meanspeed of molecules in the gas, which in turn is dependent upon thetemperature and pressure of the gas. In some embodiments, the ambienttemperature and pressure of the gas can be controlled to best match theangles of the blades.

One problem that can arise when performing direction or speed selectionis backflow from inside the device out of the input ports or past theturbine blades. One solution to this problem is to arrange the inputports and blades to reduce outflow. In FIG. 21, blades 72 are thickenedat their bases to create funnel-shaped channels that help preventoutflow.

Rotor/Stator Based Speed Selection Embodiments

FIGS. 22A to 22D illustrate a two stator and one rotor device that cangenerate hotter flows, cooler flows, or both from a gas. FIGS. 22A to22D are referred to collectively as FIG. 22.

FIG. 22 shows a device that generates a hotter flow, cooler flow, orboth hotter and cooler flows from a gas. The device includes structuresthat segregate molecules in the gas on the basis of the speed of thosemolecules, and structures that aggregate at least some of the segregatedmolecules into a bulk flow. The device is heteroscopic in that at leastsome of the structures that segregate the molecules are microscopic orsmaller, while the segregated molecules are aggregated into amacroscopic bulk flow.

In FIG. 22, the structures that segregate the molecules include inputstator 81, rotor 82, and output stator 83. The stators preferably aredisks that are positioned coaxially with the rotor.

In a preferred embodiment, rotor 82 flies over at least one of thestators due to Eckman airflow, similar to how a disk head flies over adisk in a computer disk drive. Alternatively, magnetic repulsion fromone or both of the stators can be used to keep the rotor in place.Normal mechanical mounting and other techniques also can be used.

The input stator includes plural microscopic or smaller input ports, oneof which is shown as port 84. The small size of the ports permitsselection of molecules moving only in a limited set of directions.Preferably, a very large number of input ports are arranged on thedevice.

Rotor 82 preferably is, is mounted on, or is part of a rotatingstructure such as the rotors in FIGS. 1 and 2. FIG. 22 shows the rotorin cross section. The arrow to the right of rotor 82 shows the directionof movement of the rotor as the structure rotates.

Rotor 82 includes plural channels for molecules that enter the inputports. Channel 85 is such a channel. The rotor channels can be largerthan the input ports. Preferably, though, the channels are microscopicsize or smaller.

This disk or rotor preferably rotates fast enough such that the inputports are moved through the gas at a speed comparable to the meanthermal velocity of the gas. The size of the input ports preferably iscomparable to the mean free path distance of the molecules in the gas.Thus, the arrangement of a particular rotor preferably is matched to arange of molecular speeds and mean free path distances corresponding toa particular range of temperatures and pressures of a gas.

The output stator includes at least one barrier arranged such thathotter molecules pass through the channels to one side of the barrierand cooler molecules pass through the channels to an other side of thebarrier. One of these barriers is shown as barrier 86. Representativehotter molecules are shown with small empty circles, and representativecooler molecules are shown by small filled circles.

In the device shown in FIG. 22, one or more macroscopic ducts aggregatethe hotter molecules, the cooler molecules, or both the hotter and thecooler molecules into separate bulk flows. Macroscopic duct 87represents one of these ducts.

Each subfigure in FIG. 22 illustrates different steps in segregating andaggregating gas molecules according to this embodiment of the invention.

In FIG. 22A, unsorted molecules are present above input stator 81. Thesemolecules are undergoing normal thermal motion, which is random motionin all directions.

Molecules possessing downward speed pass through port 84 of input stator81 in FIG. 22B. These molecules can then enter channel 85 of rotor 82.

Depending on the molecules' velocities in the downward direction (i.e.,the direction of the axis of rotor 82), the molecules take differentamounts of time to pass through the channels in the rotor. Hottermolecules tend to have higher downward velocities, so the hottermolecules tend to pass through the channels faster. Cooler moleculestend to have lower downward velocities, so the cooler molecules tend topass through the channel slower.

Barrier 86 is positioned so that hotter molecules that exit the channelfaster pass to one side of the barrier, while cooler molecules that exitthe channel slower pass to another side of the barrier. Thus, as shownin FIG. 22D, hotter (faster) molecules exit to one side of barrier, andcooler (slower) molecules exit to the other side of barrier. Macroscopicducts 87 aggregate like molecules, preferably from a very large numberof channels, and transport those molecules to one or more output ports(not shown). As a result, bulk flows with different temperatures aregenerated.

One concept useful for understanding the operation of the device shownin FIG. 22 is “slip.” Slip is relative motion between a spinning rotorand gas molecules in contact with the rotor. In some systems, no slipoccurs because gas molecules in contact with the rotor tend to stick tothe rotor. However, in FIG. 22, input stator 81 prevents the gasmolecules from sticking to rotor 82. As a result, slip occurs, and themolecules can pass into the channels of the rotor.

At the output (not shown) of the device in FIG. 22, the macroscopicducts preferably generate a bulk flow of gas molecules. Because of thisbulk flow, slip considerations are less important at the output.

The device shown in FIG. 22 segregates molecules primarily on the basisof their downward (i.e., vertical) velocities. However, gas moleculesalso might have horizontal (e.g., along the rotor radius) velocities,even after passing through channels in the rotor. The output stator caninclude extra barriers to segregate and aggregate molecules based ontheir radial velocities.

Thus, FIG. 23 shows an arrangement wherein the output stator includesbarriers 89 arranged in pairs. Each pair is arranged such that hottermolecules pass through the rotor to outside of the pair of barriers andcooler molecules pass through the rotor to between the pair of barriers.

In more detail, slower and therefore cooler molecules with smallerradial velocities tend not to travel far in the radial direction. Thesemolecules aggregate between barriers 89 of the output stator.

Faster and therefore hotter molecules with larger radial velocities cantravel beyond barriers 89. Thus, these molecules aggregate on eitherside of the barriers.

Macroscopic ducting can be used to redirect the cooler and hotteraggregated molecules to desired output ports (not shown).

FIGS. 24A to 24C show possible features for an output stator for adevice that performs speed selection. FIGS. 24A to 24C are referred tocollectively as FIG. 24.

In FIG. 24, stator 101 is an output stator akin to output stator 83 inFIG. 22. Likewise, barrier 102 is a barrier akin to barrier 86 shown inFIG. 22. Thus, faster (i.e., hotter) molecules pass to the left ofbarrier 102, and slower molecules pass to the right of barrier 102.

The faster molecules pass through downward directed port 103 foraggregation and output below stator 101, as shown in FIG. 24C. In oneembodiment, the molecules are aggregated simply by passing out of manyports such as port 103. In another embodiment, macroscopic ducts 104situated in or below the stator can aggregate the molecules from pluralsuch ports.

Slower (i.e., cooler) molecules are redirected by angled surface 105into a radial direction, as shown in FIG. 24B. The impact with theangled surface also can slow the molecules, possibly cooling themfurther. The redirected slower molecules pass through radially directedport 106 for aggregation and output radially from stator 101, as shownin FIG. 24C. In one embodiment, the molecules are aggregated simply bypassing out of many ports such as port 106. In another embodiment,macroscopic ducts 107 situated in or beside the stator can aggregate themolecules from plural such ports.

In a preferred embodiment, output stator 101 includes macroscopicducting to transport aggregated cooler molecules into bulk flowsradially away from the device. Likewise, output stator 101 preferablyincludes macroscopic ducting to transport aggregated hotter moleculesinto bulk flows downward from the device.

The arrangement shown in FIGS. 24A to 24C can be modified so that coolermolecules exit downward, while hotter molecules exit radially. Forexample, the angled surface could be placed on the left in FIG. 24A.

FIG. 25 shows a possible aggregation and ducting arrangement for therotor/stator embodiment.

In FIG. 25, molecules enter input stator 108 (akin to input stator 81 inFIG. 22), pass through rotor 109 (akin to rotor 82 in FIG. 22), and aresegregated and aggregated by output stator 110 using structures such asthose shown in FIG. 24. Other different structures can be use withoutdeparting from the invention.

FIGS. 26 to 28 show possible variations of the rotor/stator embodiment.

In the embodiments shown in FIGS. 22 to 25, molecules are segregatedinto two groups: hotter and cooler. However, molecules can be segregatedinto plural different groups based on their velocities. Thus, FIG. 26shows input stator 121, rotor 122, and output stator 123 configured togenerate plural different flows.

Input stator 121 is akin to the input stators already discussed. Rotor122 can also be of the same type as those discussed above. However, FIG.26 shows an alternative construction, in which the rotor includes pluralblades spaced apart to form channels. The angle of these bladespreferably is chosen based on the mean speed of molecules in the gas,which in turn is dependent upon the temperature and pressure of the gas,and the speed at which the blades move through the gas. In someembodiments, the ambient temperature and pressure of the gas can becontrolled to best match the angles of the blades.

Output stator 123 includes plural different output paths. Fastermolecules reach one of these paths after less travel distance for therotor blades, while slower molecules reach one of the paths after moretravel distance for the rotor blades. In FIG. 26, the rotor is movingfrom left to right (indicated by the arrow). Thus, faster (hotter)molecules exit more leftward output paths in stator 123, and slower(cooler) molecules exit more rightward output paths in stator 123. Thearrangement of paths preferably is periodic, repeating relative to eachinput port for input stator 121.

FIG. 27 is arranged in a somewhat similar manner as FIG. 26, except thatinput stator 124 includes plural input ports. Rotor 125 again isconstructed from blades that form channels, and output stator 126includes plural output paths. Relative speeds of molecules output by thepaths are represented by arrows, with longer arrows representing fastermolecules.

Another feature shown in FIG. 27 is that input stator 124 has longerangled parallel input ports 127. Preferably, these ports are angled inthe direction of rotor movement and have a length on the order of themean free path distance for the gas being processed. This arrangementrestricts input molecules to those already moving in the direction ofthe rotor, which improves the degree of segregation of molecules by thedevice. Restriction of the input molecules in this fashion is referredto as “collimation.”

One problem that can arise with the heteroscopic devices is backflowfrom inside the device out of the input ports or past the blades. Onesolution to this problem is to arrange the input ports and turbineblades to reduce outflow. For example, in FIG. 28, input port 130 isfunnel shaped to help prevent outflow.

Interchangeability of Features

Each of the embodiments discussed herein can benefit from structures andarrangements described for the other embodiments.

Alternative Embodiments

Many of the foregoing embodiments are discussed in the context ofrotational motion. Application of many of these concepts to linearmotion through a gas would not require any further invention. Forinstance, the turbine blades could be mounted on an element that moveslinearly through the air. An example of such an element would be aradiator of a vehicle.

Throughout this application, the rotor was assumed to be oriented with avertical axis for ease of discussion. However, the invention is equallyapplicable to any other orientation. If another orientation is used,terms such as “downward,” “below,” “vertical,” etc. should be read asbeing re-oriented in accordance with that orientation.

Furthermore, although preferred embodiments of the invention aredisclosed herein, many variations are possible which remain within thecontent, scope and spirit of the invention, and these variations wouldbecome clear to those skilled in the art after perusal of thisapplication.

1. A method of generating a flow of gaseous matter from a gas,comprising the steps of: selecting molecules from the gas on ananoscopic or mesoscopic scale; and generating the flow from theselected molecules; wherein the molecules are selected based on thedirection of movement of the molecules or based on the velocities of themolecules.
 2. A method as in claim 1, wherein the gas is air.
 3. Amethod as in claim 1, wherein the molecules are selected from the gas athigher than near-vacuum pressure.
 4. A method as in claim 1, wherein themolecules are selected from the gas at atmospheric pressure.
 5. A methodas in claim 1, wherein the molecules are selected by nanoscopic ormesoscopic blades moving at a velocity comparable to a mean free pathdistance of the molecules in the gas.
 6. A method as in claim 5, whereinthe blades are mounted on or in a rotating structure.
 7. A method as inclaim 6, wherein the rotating structure is a circular airfoil.
 8. Amethod as in claim 5, wherein the blades are mounted on or in a surfacemovable substantially linearly through the gas.
 9. A method as in claim8, wherein the surface is a radiator of a vehicle.
 10. A method as inclaim 5, wherein the blades are formed from microscopic or nanoscopicholes in a substrate.
 11. A method as in claim 5, wherein bottoms of theblades feed into macroscopic flow ducts.
 12. A method as in claim 5,wherein the blades form funnel shaped input ports.
 13. A device thatgenerates a flow of gaseous matter from a gas, comprising microscopic ornanoscopic blades or edges that, when moved through the gas, selectmolecules from the gas on a nanoscopic or mesoscopic scale, wherein theselected molecules combine to generate the flow; and wherein themolecules are selected based on the direction of movement of themolecules or based on the velocities of the molecules.
 14. A device asin claim 13, further comprising ducts that combine the selectedmolecules to generate the flow.
 15. A device as in claim 13, wherein thegas is air.
 16. A device as in claim 13, wherein the molecules areselected from the gas at higher than near-vacuum pressure.
 17. A deviceas in claim 13, wherein the molecules are selected from the gas atatmospheric pressure.
 18. A device as in claim 13, wherein the blades oredges further comprise nanoscopic or mesoscopic blades that are moved ata velocity comparable to a mean free path distance of the molecules inthe gas.
 19. A device as in claim 18, further comprising a rotatingstructure on or in which the blades are mounted.
 20. A device as inclaim 19, wherein the rotating structure is a circular airfoil.
 21. Adevice as in claim 18, further comprising a surface that movessubstantially linearly through the gas, wherein the blades are mountedon or in the surface.
 22. A device as in claim 21, wherein the surfaceis a radiator of a vehicle.
 23. A device as in claim 18, wherein theblades are formed from microscopic or nanoscopic holes in a substrate.24. A device as in claim 18, wherein bottoms of the blades feed intomacroscopic flow ducts.
 25. A device as in claim 18, wherein the bladesform funnel shaped input ports.